conflicting declaration ‘int a[4]={1,2,3,4}'

This error occurs when there are multiple declarations for the same variable or array with different initializations. In this case, the variable or array 'a' is declared twice with conflicting initializations.

To fix this error, remove one of the declarations or make sure that they have the same initialization values. For example:

int a[4] = {1, 2, 3, 4}; // correct initialization
int a[4] = {5, 6, 7, 8}; // conflicting initialization

or

int a[4]; // declare array
a[0] = 1;
a[1] = 2;
a[2] = 3;
a[3] = 4; // initialize array

Note that the second method requires separate initialization statements for each element in the array.